Thursday, October 1, 2026
McIntosh Lake, located near the unincorporated community of McIntosh, is experiencing a toxic algae bloom, the Thurston County Public Health and Social Services Department said in an announcement on Tuesday, Aug. 5.
The county health department stated that lab results of lake water samples collected on July 30 showed that microcystin toxin levels were at 9.2 micrograms per liter (µg/L).
The Washington State Department of Health (DOH) recommends issuing a warning if recreational lakes have microcystin levels of 8 μg/L or higher.
Health officials advise pet and livestock owners to keep their animals away from the lake.
According to the DOH, microcystins are a toxin produced by a certain species of cyanobacteria or blue-green algae. They primarily affect the liver of vertebrate animals and could cause death by liver necrosis within hours or a few days if an animal is exposed to a lethal dose.
Researchers also suspect that they are carcinogenic to humans, so continuous low-level exposure could increase the risk of cancer for humans.
People are advised not to engage in physical activities on the lake, such as swimming, wading, windsurfing or water skiing.
They are also advised not to drink from the water, touch algae-contaminated water or eat fish caught from the lake.
Even if the lake becomes visibly clear, toxic may still be present, so nearby residents are advised to wait for the county to declare the lake is safe again.
The county health department will continue to monitor the levels in the lake until they observe two consecutive weeks of levels below the state recreational guidelines. Nearby residents and people who plan to go to the lake may monitor the situation at the county’s website.
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CobraCommander
Best plan is to fire the county health official who declared it unsafe, then the problem will go away!
Wednesday, August 6, 2025 Report this
S2345S23456
Flesh eating bacteria anyone?
Thursday, August 7, 2025 Report this